The present invention generally relates to a novel locking mechanism for a convertible shoe system. Convertible shoe systems comprise footwear having many fashion looks and a variety of utilities that are achieved by mixing and matching a variety of shoe uppers with a variety of shoe soles. The shoe uppers are removably locked to the shoe soles using the novel locking mechanism of the present invention.
Convertible shoe systems are known wherein a variety of shoe uppers may be removably secured to a variety of shoe soles for achieving a multitude of functionalities and fashion looks. Such systems are disclosed in, for example, U.S. Pat. Nos. 4,839,948 and 4,461,102. These systems suffer from various shortcomings, however.
For example, U.S. Pat. No. 4,839,948 entitled xe2x80x9cConvertible Footwearxe2x80x9d discloses a variety of removable shoe uppers for a shoe sole. The mechanism disclosed for accomplishing this comprises a female member located in a side of the shoe sole and a male member attached to the shoe upper. The male and female members are engaged through the friction fit between a protrusion having a xe2x80x9ccurveaformxe2x80x9d cross-section on one of said female or male members and a recess that is also xe2x80x9ccurveaformxe2x80x9d in cross-section on the other of said female or male members (see FIGS. 5-5c and 6-6c). Alternatively, the female and male members may be made from magnetic or ferro-magnetic material so that the male and female members are engaged by magnetic attraction (see col. 6, lines 56-60). However, because the disclosed means for attaching the male and female members apparently are not sufficiently secure in their own right, pressure from the foot of the wearer upon the sole of the shoe is relied upon to prevent disengagement of the female and male members (see abstract). In particular, downward pressure from the foot is placed on the outer edges of the shoe insole as the means for maintaining the attached engagement of the male and female members. However, as explained below, reliance upon pressure from the wearer""s foot for securing the female and male members is a shortcoming with the mechanism disclosed in the U.S. Pat. No. 4,839,948.
As the inventor of the present invention has recognized, substantial pressure from the foot of the wearer should not be relied upon for preventing disengagement of the male and female members of the shoe upper and the shoe sole. For example, when one""s foot is picked up off the ground during walking there is very little if any downward pressure on sole of the shoe from the wearer""s foot. This is also true when the wearer is running or encounters non-level terrain that results in pressure being applied along a vector other than a downwards direction. In addition, different people have varied walking styles where ideal downward pressure is only sporadically produced, if at all, by the wearer""s foot. Accordingly, because of these various factors, the reliance upon substantial downward pressure from the wearer""s foot is undesirable and the shoe upper is likely to unintentionally disengage from the shoe sole while being worn with the mechanisms disclosed in the prior art. Another shortcoming of the ""948 patent is that no means are disclosed for securing the female member in the shoe sole. Accordingly, the female member could inadvertently become disengaged from the shoe sole while removing the shoe upper or during wear. Finally, examining the manner for removing the male member from the female member in the mechanism disclosed in the ""948 patent further reveals that unintentional disengagement is likely. The method of disengaging the male and female members disclosed in the ""948 patent calls for first removing foot pressure from the insole and placing an outward pressure on the shoe upper. However, this is precisely the type of forces that will be experienced during the normal walking stride and, therefore, will likely lead to unintentional disengagement of the upper from the shoe sole.
With respect to U.S. Pat. No. 4,461,102, although the problem of unintentional disengagement is allegedly addressed, the aesthetics of the shoe are severely compromised. As can be understood from even a cursory review of the figures in that patent, the means for attaching the upper to the shoe sole are clearly visible thereby detracting from the aesthetics of the shoe and limiting the number of upper styles that can be used with the shoe.
Thus, it would represent an advancement in the art if a locking mechanism were provided for securely attaching a shoe upper to a shoe sole that is both secure without relying upon substantial pressure from the wearer""s foot and capable of being placed in the shoe in a manner that does not detract from the aesthetics of the shoe. Preferably, the locking mechanism is substantially concealed when the shoe upper is attached to the shoe sole.
The applicant for the present invention has addressed the foregoing problems and has developed a novel locking mechanism for a convertible shoe system. The locking mechanism securely attaches a shoe upper to the shoe sole without requiring substantial downward pressure from the user""s foot and is aesthetically pleasing in that the mechanism may be substantially concealed from view when the shoe upper is attached to the shoe sole. The shoe upper is preferably adjustable.
In one aspect of the present invention, a locking mechanism for a convertible shoe system comprising a shoe sole and a removable shoe upper is provided. The locking mechanism comprises a female member, wherein the female member has an opening and a locking clip positioned in the opening. The locking mechanism further comprises a male member that has an opening adapted to receive the locking clip of the female member. The locking clip engages the male member in a latch-type manner and prevents unintentional disengagement of the male member from the female member. One of the male and female members is attached to the shoe upper and the other of said male and female members is positioned in the shoe sole.
Preferably, the female member is positioned in a cavity formed in a sidewall of the shoe sole. The opening in the female member is preferably formed by a pair of spaced apart sidewalls, a base positioned between and integral with said sidewalls. The locking clip is integral with and projects upwardly from the base of the female member. In addition, a release member is housed in the opening of the female member. The release member functions to disengage the male and female members when pressure is applied to the release member. In particular, the release member comprises a top surface having an opening that is aligned with the opening of the male member when the male member is engaged with the female member. Thus, the locking clip of the female member projects through the opening in the release member and then through the opening in the male member. The release member further has a release surface and an underclip such that when pressure is applied to the release surface the underclip engages the locking clip thereby removing the locking clip from the opening in the male member and permitting disengagement of the male member from the female member.